Hi Chris, Steve Watson here. You didn't reply. Are both transmissions in good shape? How much do you want for either?I think the only differance in the tranny's is the length of the c/shaft. The "D" models are longer so that they use the flat sprocket as opposed to the "dished" one on the "C" models. All you have to do is get the correct sprocket then.
I have 2 complete transmissions!!!! One I know is for a "C" and the other I have to check.
Let me know if you still need it.